The Trump administration recently imposed steel and aluminum tariffs on Canada, Mexico and the European Union, all US allies. On Friday, the United States announced a 25% tariff on $50 billion of imports from China. China quickly announced plans to retaliate.

Last week, Fed Chairman Jerome Powell played down the impact that trade frictions were having on businesses' behavior.

"Right now, we don't see that in the numbers at all," said Powell at a press conference. "The economy is very strong. The labor market is strong. Growth is strong. We really don't see it in the numbers. It's just not there. I would put it down as more of a risk."